This study examines the relationship between perinatal factors and the occurrence of seizure disorders in childhood in a large, prospectively studied population. In addition to the central question of etiology, it investigates frequency, prognosis, demographic characteristics, and a number of other aspects of these disorders. Extensive hand review and classification of cases has been completed, and files created. Univariate screen of maternal, obstetric, and pediatric risk factors, and demographic analysis, have been completed, and preparation for multivariate analysis is underway. Selected topics, of particular clinical relevance are under examination. Target date for completion of a manuscript for a monograph on childhood epilepsies is July, 1978.